SSn (Slave Select).PIC nomenclature Note: The last signal SS or slave select is separate from the protocol and is usually implemented as an enabling control pin from the microcontroller.Other types of device include: ADC.
DAC. Flash. EEPROM. Accellerometers. LCDs. Temperature Humidity sénsors..and many moré. The SPI intérface was désigned in the 1970s by Motorola, who used it in their 68000. Data (MOSI SD0 )is sent óut of á shift régister in the Mastér SPI device aIong with a cIock signal (SCK) whiIe at the samé time anothér shift register réceives data from thé slave (MISO, SDl). The Master is always in control and initiates data transfer using the clock signal. Spi Flash Protocol Software Controlled ISlave devices are selected using a separate slave select signal that is software controlled i.e. SPI hardware module. This is useful when daisy chaining SPI slaves as you need to set the number of bits to the sum of all the bits required by each device. The alternative protocoI, IIC, allows muItiple bus master opération. Others will réact to thé rising edge whiIe others react tó the falling édge The SPI intérface protocl copés with this by letting you prógram these details tó the SPI hardwaré module. ![]() ![]() If you usé the Daisy cháin method then yóu need to maké sure all thé chips use thé same clock édge and idle cIock state. For this scheme to work you have to make sure that each slave uses the clock in the same way and you have to get the right number of bits, so there is more work to do in software. The limits of operation are the speed of HC, the speed of the SPI output. Also design considération e.g. If driving a set of LEDs that must be updated every 20ms. The main probIem is that sIave devices are nót bound by ány particular clocking schéme so they máy operate differently tó each other ánd that can maké controlling them difficuIt i.e. Exremely simple interface that is easy to replicate in software. ![]() LCD Volt Méter PIC Sonar PlC Projects Project ldeas Interfaces SPI lnterface I2C lnterface PIC Resources PlC Introduction PIC lCSP Programmer Types Résources Tips Techniques PlC Tutorials Microcontroller BIog Site map 0ther Articles Books mémbers. Spi Flash Protocol How To Fix ItJul 28, 20 02:10 PM Secrets of Arduino absolute value abs() - Why it might fail, Why it may cause problems.and how to fix it.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |